EP1290383A2

EP1290383A2 - Concentrating solar energy system

Info

Publication number: EP1290383A2
Application number: EP01960228A
Authority: EP
Inventors: Andreas Nöhrig
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-05-22
Filing date: 2001-05-18
Publication date: 2003-03-12
Anticipated expiration: 2021-05-18
Also published as: ATE384231T1; ES2300350T3; WO2001090662A3; US6953038B1; EP1290383B1; DE10025212A1; WO2001090662A2; IL152992A0; ZA200209466B; IL152992A; PT1290383E; AU8178001A; AU2001281780B2; DE50113510D1

Abstract

The lower edge (12) of the mirror is directly adjacent to its support plane. Seen in plan view, this edge is either straight or slightly-curved. The parabolic mirror (10) pivots up and down about a pivotal axis (36) located close to the support plane.

Description

P T / EP01 / 05743

Concentrating solar energy system

The present invention relates to a concentrating solar energy system with a reflector realized as a biaxial tracking parabolic mirror, which is carried by a base frame arranged in a supporting plane and with a receiver arranged in operation in, before or after the focal point of the parabolic mirror, the parabolic mirror also being around an axis arranged at least substantially perpendicular to the supporting plane is rotatable.

The solar energy systems that have been implemented so far can be roughly divided into three groups: photovoltaic systems that generate electricity directly from sunlight, solar collectors that take heat from the surface of the surface, and concentrating solar energy systems that bundle sunlight strongly and can generate high-temperature energy in a receiver.

The concentrating solar energy systems are characterized physically by the fact that the energy can be used on several levels. This enables efficiencies of over 70% to be achieved. For example, if heat of 600 ° C is generated, it can be used in the range of 600 ° C - 100 ° C to generate electricity. The resulting waste heat can then be used in the form of water at around 90 ° C.

These concentrating systems have the disadvantage that they have to track the sun, which can be very expensive in the case of large areas. There are three different types of concentrating solar A distinction is made between energy systems: solar tower power plants in which the sun is tracked with the help of heliostats, parabolic trough systems that only have to track the sun vertically and biaxial tracked parabolic reflectors.

Approaches for the implementation of solar energy systems and the possibility of using Stirling engines, which can be used as a drive for power generators, among other things, and possibilities for energy storage are described in the book "Stirling Machines - Basics. Technology. Application by Martin Werdich ISBN 3 - The book shows in Figure 53 a biaxial tracking parabolic reflector, which is circular in plan view and is supported by an elaborate base frame and frame mounted on it. The parabolic mirror is supported in the sun and supported by a horizontal right axis can be swiveled, which is parallel to a diameter of the parabolic mirror, which is circular in plan view, in front of its reflecting surface, in order to enable vertical tracking according to the height position of the sun, which is technically known as tracking the elevation or height. Dar- In addition, the parabolic mirror can be rotated about an axis perpendicular to the base frame. This rotation causes horizontal sun tracking.

A similar construction is known from the German utility model G 8427130.2. There comes as a reflector instead of one

Full parabloid is a partial parabloid for use that extends about 240 ° around the axis of symmetry of the parabloid. Here too, vertical tracking takes place around a swivel axis that is fixed to the base frame is arranged and that at a significant height above the base frame.

The problem with this known construction is above all the arrangement of the horizontal axis, which is used for vertical sun tracking.

Problems arise with this arrangement in that the parabolic reflector has to be mounted so high above the ground that there is sufficient ground clearance for the vertical tracking. The focus of the system is therefore very high.

In the case of large systems in which the diameter of the parabolic reflector is 10 m - 20 m, this leads to very massive, heavy designs, since the construction must also be storm-proof.

With this construction, the sensitive reflector surface cannot be easily protected against environmental influences such as precipitation. This results in a considerable cleaning effort, which also leads to increased wear on the reflector surface. Soft, inexpensive materials such as mirrored plastic foils cannot be used for the reflector layer. The mirror would go blind early.

Furthermore, it is completely unthinkable to place a system of this type on the flat roof of a normal building, since it is too heavy and protrudes too high above the house. The roof of a house is the cheapest place to install solar energy systems, because there is little shade and the otherwise unused area can be used. Furthermore, the energy transport route is very short, ie the system is suitable for decentralized energy supply. Based on this prior art, the present invention has the object to construct a biaxially tracking, concentrating solar energy system so that with much less effort than before, a higher stability of the arrangement is achieved that the parabolic mirror in the absence of solar radiation in a rest position can be brought, in which the system offers only small areas of attack for wind, is absolutely storm-proof and the reflection layer is protected from precipitation. Furthermore, the system should be able to be installed on the flat roof of a building and even be able to replace the roof, ie be able to take over the function of the roof.

To achieve this object, according to the invention, according to a first solution, the parabolic mirror has an operating lower edge, which is at least substantially adjacent to the supporting plane and is either straight or slightly curved in plan view, and that the parabolic mirror is in the area its lower edge and at least substantially parallel to the supporting plane and linearly movable over the base frame pivot axis up and down is pivotable.

The fact that the parabolic mirror is provided with a lower edge during operation, which in plan view either runs straight or is slightly curved, enables the pivot axis of the parabolic mirror to be arranged in the region of this lower edge and therefore in the immediate vicinity of the supporting plane or the base frame, so that the pivot axis, for example, only has to be arranged a little above the floor and the center of gravity of the parabolic mirror is always only just as high as is necessary above the floor. As a result, the mechanical Requirements for supporting the parabolic mirror are significantly lower than in the known arrangement, as a result of which the entire structure is simpler and easier to implement. The base frame can be used for direct support of the swivel axis, so to speak, and it is no longer necessary to produce a huge frame construction in three dimensions in order to support the biaxially adjusted parabolic mirror. Even if the parabolic mirror now presents itself as a halved parabolic mirror, i.e. as a semi-paraboloid that extends around 180 ° around the axis of symmetry, this means no loss of the effective surface of the parabolic mirror, because the length of the lower edge of the parabolic mirror and thus its effective Area can be easily increased without making the construction much heavier. Thus, the invention offers significant advantages with the same surface area as the parabolic mirror known per se.

With regard to the vertical adjustment of the parabolic mirror, according to the invention, the pivot axis of the parabolic mirror is moved over the base frame with the aid of a linear drive (actuator), in order to thereby generate the upward and downward pivoting movement of the parabolic mirror.

The following advantages, among others, reached:

- Due to the pivoting movement of the parabolic mirror, which is accompanied by the linear movement of the pivot axis of the parabolic mirror, the center of gravity of the parabolic mirror with respect to the base frame is always held approximately above the center of the base frame, so that a particular stability against attacking forces is achieved. - The arrangement of the lower edge of the parabolic mirror essentially immediately adjacent to the supporting plane in combination with the pivoting movement, which is achieved by moving the pivot axis above the base frame immediately adjacent to the supporting plane, the stability of the construction is further increased.

- For vertical sun tracking by changing the position of the parabolic mirror combined with the swiveling movement, the parabolic mirror is only ever raised as high as is necessary for this purpose, which in turn increases stability, i.e. the focus always remains in a low position.

- The displaceability of the swivel axis over the base frame enables the paraboloid to be closed, so that the mirror surface points downward and is therefore protected against unfavorable environmental influences.

Because the said pivot axis is arranged in the vicinity of the base frame, the parabolic mirror can be swung down so far that it is used as a roof and the reflecting surface faces downward and is therefore protected against environmental influences, such as precipitation, etc. In this swung-down state, the parabolic mirror and the solar energy system itself are positioned in such a way that there are only small areas of attack for wind and the system is absolutely storm-proof.

As a result, the parabolic mirror can be swung down relative to the base frame so far that it is on the supporting base or on the foundation, a surface or a wall adapted to the outline of the parabolic mirror is tight or flush. The parabolic mirror can then be attached to the supporting base with simple means, so that it is attached absolutely storm-proof.

An elongated support structure preferably extends along the lower edge of the parabolic mirror, which both stiffens the parabolic mirror and supports the pivot axis.

In this way, a mechanically sophisticated connection of the

The swivel axis on the parabolic mirror and the parabolic mirror itself can be built even more easily, since the supporting structure contributes to its stiffening.

To realize the rotary movement around the vertical axis, the base frame can be rotated on a circular path by means of rollers or wheels. The castors or wheels are attached to the base frame itself. This track can be formed on the floor or on a foundation or on walls. Alternatively, rollers or wheels can be arranged at discrete locations along the circular path and supported on the floor or on a foundation. In this example, the base frame would comprise a circular ring that can run around on the rollers or wheels. If the wheels or castors are attached to the base frame and there is a level, solid base available, for example the concrete ceiling of the top floor of a house or a flat roof, this base forms the circular path. The wheels can then sit directly on this surface. Such constructions can be realized inexpensively and the inherent strength of the floor or of foundations and walls enables one solid support of the parabolic mirror. It should be stated at this point that although the base frame or the track will usually be arranged horizontally, it is also possible without further ado to mount the base frame or the track parallel to the ground on an inclined plot of land or on a slope to support the corresponding inclined wall, for example in the event that a higher inclination of the roof should be desired for some reason in the swung-down state. With such an inclined position of the base frame, one only has to take appropriate measures to ensure that the base frame is secured against slipping.

It is particularly expedient if the base frame is arranged inclined to a horizontal plane, with the base frame in the region of the pivot axis, i.e. in the swiveled-up state of the parabolic mirror. front, higher than rear, i.e. in the field of

Swivel axis when swiveled down. This can include can be achieved in that the wheels, which in the swung-up state of the parabolic mirror in the region of the swivel axis, i.e. are arranged at the front of the base frame, have a larger diameter than the wheels, which in the swiveled-down state of the parabolic mirror in the region of the swivel axis, i.e. are arranged at the rear of the base frame.

This ensures that when the sun is high, especially at the equator, the paraboloid in the swung-up state reaches a horizontal or almost horizontal position. The required amount of pivoting movement can be limited by the forward inclination of the base frame, which has a positive influence on the overall geometry. According to a second approach, the present invention is characterized in that the parabolic mirror can be swiveled up and down about a lower swivel axis arranged in the region of the support plane or at a distance above or below it, the swivel axis being in a plane parallel to the support plane or in the supporting plane is arranged displaceably and the displacement of the pivot axis leads to or contributes to the corresponding pivoting movement of the parabolic mirror. In other words, the parabolic mirror can be pivoted up and down about a pivot axis supported by the base frame and the pivot axis can be displaced in a plane parallel to the supporting plane for carrying out the corresponding pivoting movement.

The displacement of the swivel axis in order to swing the parabolic mirror up or down has the decisive advantage that the center of gravity of the parabolic mirror can always be arranged above the base frame and preferably always in the area of the vertical axis of rotation, so that a very stable one Arrangement results and the construction of the base frame does not have to be carried out excessively heavy to take into account a changing position of the center of gravity, since the center of gravity remains in or approximately in a constant position.

To implement the pivoting movement of the parabolic mirror, the latter is connected to the base frame via a linkage arrangement and the pivot axis is designed to be movable over the base frame. In a first variant of the invention, the linkage arrangement can consist of at least one steering arm which at one end in the central region of the pair Rabolspiegel is pivotally articulated on the back and at the other end on a base which is carried by the base frame and arranged behind the parabolic mirror. The base can be clearly above the base frame, for example at a height which is slightly above the maximum height of the parabolic mirror when swung down. As a result, the steering arm can be designed in a straight line, as a result of which it can be implemented inexpensively and with low weight. However, this is not absolutely necessary and it can also be advantageous to arrange the base lower or even below the base frame, as will be explained in more detail later.

Two or more steering arms are preferably provided, which are pivotably articulated at respective points on the rear of the parabolic mirror and at respective support points. The use of at least two such steering arms leads to a stable construction which counteracts the inclination of the parabolic mirror to deformation and thus also contributes to a lightweight construction.

In the area of the support point of each steering arm on the base frame, a recess is preferably provided in the parabolic mirror, which extends from the intersection of the curvature of the parabolic mirror with the supporting structure of the parabolic mirror to an imaginary line between the pivot axis of the parabolic mirror and the articulation axis of the respective steering arm on the parabolic mirror or one parallel line is sufficient. This stiffens and strengthens the parabolic mirror. Furthermore, the recesses) allow the support point to be moved downward from each steering arm, since the recess can accommodate the steering arm, which makes it possible to swing the parabolic mirror up so far that the horizontal position is reached.

Moreover, it is advantageous if the lower edge of the parabolic mirror during operation has cutouts in the area of the base frame. This prevents the parabolic mirror from abutting the base frame in the pivoted-open state and allowing a greater pivoting movement of the parabolic mirror.

Instead of attaching the steering arm or the steering arms to the back of the parabolic mirror, he or she can be pivoted at one end in the central region of the parabolic mirror on its reflecting inside and at the other end on a base which is supported by the base frame and in pivoted-down state of the parabolic mirror is adjacent to the position assumed by the upper edge of the parabolic mirror in the pivoted-up state. In this arrangement, too, two or more steering arms are preferably provided, which are pivotably articulated at respective points on the inside of the parabolic mirror and at the respective support point on the base frame. This arrangement of the steering arm or the steering arms on the inside of the parabolic mirror leads to the advantage that the entire mechanism is arranged below the parabolic mirror in the pivoted-down state and is thus protected in this rest position. It makes sense to introduce a special resting position since the system only has to be active when the weather is nice, i.e. sunshine. There is no sun shining during rainfall and storms, which is why the system could also serve as a roof, since a firm roof is only needed in relation to the weather when the sun is not shining. An actuator driven by a drive motor is preferably provided for moving the pivot axis on the base frame. There are several options for realizing the actuator. On the one hand, the actuator can be a threaded spindle mounted on the base frame, which is located in a corresponding thread or in a corresponding threaded nut or in a push block that belongs to the structure supporting the pivot axis.

A thrust block is preferably provided for each pivot bearing on the pivot axis. A threaded spindle is thus assigned to each pivot bearing of the pivot axis and engages in the area of the thrust block of the parabolic mirror or on the supporting structure of the parabolic mirror. If several threaded spindles are provided, they must be driven synchronously, which can be done, for example, by means of a chain drive that drives both spindles at the same time.

When using several thrust blocks carrying the swivel axis with a number of actuators which deviate from the number of thrust blocks, the thrust blocks can be firmly connected to one another and the actuator or the actuators can be connected to the compound in such a way that the driving forces are at least essentially are evenly distributed over the push blocks.

As an alternative to using threaded spindles, the actuator can be a chain drive, the chain of which is two

The base frame of the pivoted sprockets runs and is attached to the parabolic mirror at one point in the area of the pivot axis. For example, a chain drive can be assigned to each pivot bearing of the pivot axis and the chain drives can be driven synchronously, for example by driving the drive sprockets via a common shaft.

The actuator can also be implemented differently. For example, the actuator can be a hydraulic drive or a toothed rack, toothed belt or chain can be attached to the base frame and mesh with a driven pinion that is attached to the thrust block or to each thrust block. For the movement of the push blocks, revolving cable pulls are also possible, which are preferably designed with at least two rollers so that one end of the cable is wound up and the other end is unwound at the same time.

It is not absolutely necessary to provide a drive for each thrust block, after all it is sufficient if a drive is provided on one thrust block and on another or on another

Shear blocks guide devices are provided which are guided on guide rods or rails on the base frame. No matter which actuator is selected, it is preferably designed so that the mirror remains in a controlled position. This can be achieved in that the actuator is designed so that it is not reversible, ie in such a way that the motor can drive the parabolic mirror, forces which are exerted on the parabolic mirror but cannot lead to an adjustment thereof. This can also be achieved in that the drive motor acts as a brake or has a brake in order to hold the actuator in the position it is approaching. Is preferred for Fixing the thrust blocks used the self-hold, which can be reached, for example, in a worm gear.

It is particularly expedient if a spring or a plurality of springs, for example in the form of a rubber cable or a plurality of rubber cables, is or are provided in order to support the actuating force of the motor provided for pivoting the parabolic mirror or of the motors provided for pivoting the parabolic mirror. As a result, the actuating force to be supplied by the motor or motors can be reduced, so that the motor or motors and the entire construction can be built more easily. A conventional garage door drive can advantageously be used for the pivoting movement of the parabolic mirror, as a result of which the actuator can be implemented at low cost.

It is particularly expedient if the receiver is carried on one end of a support arm, the other end of which is articulated in the region of the lower edge of the parabolic mirror, preferably on the support structure mentioned, and can also be pivoted open when the parabolic mirror is swung up. The receiver can be swiveled up simply by placing the support arm on the support structure mentioned. This means that no separate control device is required for the receiver. This arrangement also has the advantage that the receiver is always covered and protected by the parabolic mirror when it is swung down. With heavy receivers, a rope can be stretched between the receiver and the inside of the mirror so that the high lifting forces are absorbed.

It is also possible to provide one or more springs, for example in the form of a rubber cord or a plurality of rubber ropes, which from Receiver runs to the front part of the base frame and is or are tensioned when the parabolic mirror is pivoted up. This creates a torque on the parabolic mirror. This has the advantage that the springs or rubber cables, when the parabolic mirror is opened to the maximum, absorb a large part of the holding forces and the actuators are supported when the parabolic mirror is swung down. Especially for the movement of the parabolic game from the maximally swung-up state into a further swung-down state, a relatively large actuating force is required, which now only has to be generated in part by the actuator due to the spring force.

Furthermore, the receiver and the steering arms are held in their desired position when the parabolic mirror is open.

It is also possible to provide one or more springs, for example in the form of a rubber rope or a plurality of rubber ropes, which run or run from the front of the base frame to a support structure for the parabolic mirror arranged in the region of the lower edge of the parabolic mirror during operation swung down state of the parabolic mirror is or are tensioned. These springs, which are no longer tensioned when the parabolic mirror is swung up, deliver a force during the initial swiveling up movement of the parabolic mirror, which supports the actuator and also reduces the maximum required force with the advantages mentioned above.

In principle, the external shape of the parabolic mirror is not critical. In plan view, this can be approximately semicircular, rectangular or rectangular be rounded corners, in the latter case in particular the corners facing away from the lower edge are rounded. A slight curvature of the lower edge seen in plan view is limited in its extent by the ground clearance in the area of the base frame. It is particularly preferred if the parabolic mirror has a shape that results from the cutting curve between a semi-parabolic rotating body and a plane that is transverse to the axis of rotation of the rotating body. This construction ensures that the parabolic mirror has the smallest possible depth.

Particularly preferred options for producing the parabolic mirror result from claims 35, 38 and 62. It is particularly expedient if a liquid metal, for example zinc, is used as the heat carrier in the receiver. Molten salts, thermal oil, water or a hot gas engine (Stirling engine) can also be used directly. With the help of a secondary reflector, the solar radiation energy could be concentrated directly on a storage located in or on the center of the base frame. Zinc could be a particularly good storage medium here, since it melts at 420 ° C and absorbs 111 kJ / kg during a phase change. Solar cells can also be attached to the focal point for direct power generation.

Particularly preferred embodiments of the invention can be found in the patent claims.

The invention is explained in more detail below with reference to two exemplary embodiments which are shown in the accompanying drawings. Show it: Figure 1 is a plan view of an inventive concentrating

Solar energy system with lowered parabolic mirror,

Figure 2 is a view of the concentrating solar energy system according to the invention of Figure 1 seen in the direction of arrow II of Figure 1, i.e. seen from behind.

3 shows a side view of the solar energy system according to the invention from FIG. 2 seen in the direction of arrow III,

FIG. 4 shows a front view of the solar energy system according to the invention according to FIGS. 1 to 3 in the pivoted-up state,

characters

5A-5E a sketch sequence to explain the swinging up of the

Parabolic mirror of the solar energy system according to FIGS. 1-4,

FIGS. 6A-6C show a sketch series similar to the sketch series 5A-5E, but for a further particularly preferred embodiment variant of the solar energy system according to the invention,

FIGS. 7 and 8 show two further examples of a parabolic mirror according to the invention with built-in stiffening triangular frames,

FIGS. 9A and 9B drawings corresponding to FIGS. 5A and 5D to explain a further variant of the solar energy system according to the invention, FIGS. 10A and 10B drawings corresponding to drawings 6A and 6C to explain a further variant of the solar energy system,

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11 A - 11 J drawings to explain various options for

Realization of a parabolic mirror according to the invention,

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12 A-12D drawings which indicate various possibilities of how a parabolic mirror according to the invention can be produced from segments,

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13A-13H drawings which show a technical possibility according to the invention for producing a parabolic mirror from individual segments consisting of extruded foam, FIGS. 13B and 13C showing views of the segment of FIG. 13A corresponding to the arrows 13B and 13C, FIG. 13D

FIG. 13E, which corresponds to the illustration in FIG. 13C, but with the connecting element in accordance with FIG. 13D, FIG. 13, which is also made of extruded polystyrene or polyurethane foam and can optionally be cut out of the segment according to FIG. 13A

13F shows a plan view of a segment similar to FIG. 13A, but with connecting elements according to the invention according to FIG. 13D, FIG. 13G shows a representation corresponding to the lower right sector 142 according to FIG. 12B and FIG. 13H shows the connection of two smaller segments. speaking to each other the section plane 13H-13H according to FIG. 13G,

14 shows a plan view of an arrangement according to the invention similar to FIG. 1, but without a parabolic mirror and the steering linkage connected therewith, in order to illustrate a possibility of horizontal tracking,

FIGS. 15A to 15C are drawings which show a drive according to the invention which can be used for the vertical tracking of the parabolic mirror according to the invention, FIG. 15B showing a sectional drawing corresponding to the sectional plane 15B-15B in FIG. 15A and FIG. 15C a plan view of FIG. 15A in the direction of arrow 15C,

FIG. 16 shows a plan view corresponding to FIG. 15C, but of a further arrangement according to the invention for the vertical adjustment of the parabolic mirror, and

Figures 17,

18A, 18B,

19A, 19B,

19C, 20A, 20B, 21,

22A, 22B and 22C show modifications of the constructions described so far which are perceived as being particularly advantageous.

FIG. 1 first shows a top view of the back of a parabolic mirror 10 according to the invention in the swung-down state. From this representation, one can see the lower edge 12 of the parabolic mirror, which appears straight in plan view in operation, and its substantially semicircular shape. The parabolic mirror 10 is attached to a base frame 14 in a manner still to be explained, the base frame consisting of two side members 16 and 18, which are supplemented by means of cross members 20 and 22 to form an approximately square frame, two diagonal struts 24 and 26 being necessary Ensure the stability of the base frame. At the four corners of the base frame in the area of the connection points between the corner beams 16, 18 and the cross beams 20, 22 there are four wheels 28 which can run on a circular foundation 30, in order thus to enable the base frame to be rotated about the vertical axis 32 ,

It can be seen from FIG. 2 that the parabolic mirror 10 has a relatively flat, curved shape in the swung-down state and in front view, the maximum depth of which is indicated by T in the middle.

In a practical embodiment, the length of the lower edge 12 of the mirror can be approximately 8 m, for example, so that the radial height of the mirror is approximately 4 m and the maximum depth T according to FIG. 2 is approximately 100 cm. It is readily apparent from Figure 2 that the overall construction has a very low overall height when swung down and that the base frame can be built correspondingly low.

The side view according to FIG. 3 also shows that a support structure 34 adjoins the lower edge 12 of the parabolic mirror and through the connection of the parabolic mirror along the entire length of the support structure 34, ie along the entire curved surface in FIG Figure 2, the parabolic mirror is stiffened accordingly by this support structure 34. Ie the open area of the paraboloid is closed by 34 in the third dimension and thus stiffened considerably. For high stability requirements, spoke-like struts or cable bracing can be used.

The support structure or stiffener 34 also serves for the pivotable suspension of the parabolic mirror about the pivot axis 36, which is defined by pins which are mounted or mounted in tabs 38 attached to the support structure and in push blocks 40 which are displaceably guided on the base frame 14. As can be seen from FIG. 1 and FIG. 2, two thrust blocks 40 are provided in this example, each of which is arranged in one of the longitudinal beams 16 or 18 realized as a U-shaped rail and for pivoting up or downward pivoting of the parabolic mirror about the pivot axis 36 along the respective one U-shaped rails 16, 18 are displaceable, as is readily apparent from FIGS. 5A-5E.

From the side view of Figure 3 you can also see a steering arm 42 which is pivoted at one end, the left end 44 in Figure 3, pivotable about the articulation axis 46 on the back of the parabolic mirror in its central region and at its other, in Figure 3 right end 48 is articulated at a base 50 about a further pivot axis 52. The support point 50 is formed by a support post 54 which is fastened to the base frame 14 and is stiffened by a corresponding strut 56. The base in Figure 3, ie the position of the pivot axis 52, is preferably not necessarily above the base frame. It is important that the point 46 in FIG. 3 in the opened state (see FIGS. 5B to 5E) always have to remain above the line between 52 and 36 in FIG. 3, since otherwise the mirror will no longer be closed. that can. The pushing motion would otherwise produce a downward torque. The height of the support point 52 in FIG. 3 thus influences the maximum opening angle of the mirror. This can cause problems near the equator. The optimal height of 52 in FIG. 3 is probably given at the same height 36 in FIG. 3. Practice has to show that. Because the articulation point 52 is approximately at the maximum height of the parabolic mirror in the swung-down state, the steering arm 42 is at least essentially straight and could be made completely straight if the support point 52 were placed slightly higher than in FIG. 3 shown. In fact, two steering arms 42 are provided, as can be seen in FIGS. 1 and 2, and they are arranged on the main frame immediately adjacent to the push blocks 40.

3 there are two support arms 58, only one of which can be seen in FIG. 3, but both support arms can be seen in FIG. 4. Each support arm 58 is pivotally articulated at one end on the parabolic mirror 10, specifically at an articulation axis 60 in the region of the transition between the lower edge 12 and the support structure 34 and is connected at its other end to a receiver 62 which, in the pivoted-up state of the Parabolic mirror according to Figure 4 is located in the focal point of the parabolic mirror.

The swiveling up or swiveling down of the parabolic mirror 10 is explained in more detail below with reference to FIGS. 5A-5E, FIG. 5A corresponding to FIG. 3, but only on a smaller scale. This is the rest position of the parabolic mirror 10, ie the completely folded-down state, and it is evident from this figure Visible that the receiver 62 and the support arms 58 and the entire area below the parabolic mirror are covered and protected by this. The reflecting surface of the parabolic mirror, on the underside of which is shown in FIG. 5A, is also protected in this way in the rest position.

If the sun is now shining, the movement of the

Thrust block 40 provided in the direction of arrow 70, whereby the parabolic mirror 10 is forced, due to the linkage arrangement 42, to pivot upward in the arrow direction 72 about the pivot axis 36 of the thrust block 40 in the clockwise direction. During this original pivoting movement, the receiver 62 remains on the base frame (on the cross member 20) since the support arms 58 pivot about the pivot axis 60, but is pushed forward with the pivot axis 60. A guide rail can also be attached to the base frame for the support of the receiver and rollers of the sliding blocks on the receiver.

When the push block 40 is shifted to the left, the position according to FIG. 5C is reached, where the parabolic mirror 10 is almost upright and one can see that in this position the support arms 58 have come into contact with the support structure 34 and that the receiver 62 this is already slightly raised. The receiver 62 is now at the focal point of the parabolic mirror.

As the push blocks 40 progressively move to the left along the main supports 16 and 18, the parabolic mirror moves more and more backwards according to FIG. 5D and then FIG. 5E, which represents the maximum pivoting angle of the parabolic mirror 10. This pivoting movement about the pivot axis 36 is the vertical tracking of the parabolic mirror, which is necessary to the respective Follow the height of the sun so that the maximum sun intensity is received and concentrated on the focal point receiver 62.

When the sun sets in the sky in the afternoon, the pivoting angle is increasingly reduced by moving the push blocks 40 to the right from the maximum position according to FIG. 5E, so that, for example, the intermediate position according to FIG. 5D and then according to FIG. 5C is reached and the sunset is followed by the parabolic mirror becomes. During the rotational movement about the pivot axis 36 for the

Tracking of the parabolic mirror depending on the height of the sun, a simultaneous rotary movement about the vertical axis 32 (only shown in FIG. 1 and FIG. 5D) ensures the horizontal tracking, i.e. the rotation according to arrow 74.

If, at the end of the day or, for example, when there is snow or rain, there is no longer sufficient sunshine, the fully pivoted-down state according to FIGS. 3 and 5A is approached and the parabolic mirror 10 now functions as a roof.

A wall or support surface can be built according to the shape of the paraboloid so that the paraboloid lies directly, flat and completely sealing. Closures can also be attached to this wall that permanently connect the paraboloid to it, so that the roof is absolutely tight (up to airtightness!) And storm-proof. The paraboloid is thus also against pressure from above, e.g. secured in case of snow load. Dome effect!

One can now easily imagine that there is a swimming pool or part of a swimming pool below the parabolic mirror in FIG. det, which can be heated with energy that is collected by the parabolic mirror and focused on the receiver 62. However, the roof in the form of the swung-down parabolic mirror 10 could also be the roof of a house or a roof area of a house. Otherwise, the mirror in the swung-down state can also be used to illuminate the covered area, because it is only necessary to arrange a single light source in the region of the focal point of the mirror, ie somewhat below reference number 30 in FIG. 3, in order to use the parabolic mirror to Illuminate the room relatively evenly. The floodlights, which are now very inexpensive, would be ideal for this.

FIGS. 6A-6C now show an alternative embodiment in which both the thrust blocks 40 and the steering arms 42 in the swiveled-down state of the parabolic mirror 10 according to FIG. 6A are accommodated completely below the parabolic mirror and are therefore optimally protected. This embodiment is superior to the first in almost every respect and is therefore preferred in practice. This construction is unbeatable as a house roof. A rectangular house can also be covered with two smaller systems, which will be described later with reference to FIG. 11E. In this embodiment, the unfavorable leverage in the two extreme positions (fully closed and fully open) can easily be compensated for with a vertical rod and an additional cable. In the case of such a design, the vertical rod would have to be arranged in the region of the rounded edge of the parabolic mirror in FIG. 1 and fastened to the base frame. The rope would have to be designed so that it extends from a deflection roller at the top of the rod approximately perpendicularly downwards to the center of the front edge of the parabolic mirror. The parabolic mirror can then be next be lifted from the closed position until the leverage ratios become more favorable. In the extremely inclined position according to FIG. 5E, the rope can be pulled again to support the closing movement. The rope can become slack between the two positions or only remain slightly pretensioned. The rod could also be used as a support for a high-altitude liquid storage with gravity circulation.

The same reference numerals are used for the embodiment according to FIGS. 6A-6C as for the embodiment according to FIGS. 1-5, and the same description applies to parts having the same reference numerals as in connection with FIGS. 1-5 because something else is said.

As can be seen from FIGS. 6A-6C, the steering arms 42, of which there are also two (only one of which is shown in the figures), are at one end on the inside of the parabolic mirror 10 at 46 and at the other End pivoted at 52 on the base frame 14. The thrust blocks 40 are now on the "inner" side of the support structure 34. In this case, the openings 128 shown in FIG. 1 II must be provided in the support structure 34, since when the paraboloid 10 is pivoted open, the thrust blocks 40 pass through the support structure 34 move through, ie on the left side of this support structure in Figure 6A. In this embodiment too, the receiver 62 is carried by two A-shaped support arms 58, which are pivotably articulated on respective articulation axes 60 in the area of the lower edge 12 of the parabolic mirror during operation and its connection to the support structure 34. The position of the individual suspension points must meet the following criteria in order to enable opening and closing. In the variant shown in FIGS. 1 to 5, the distance between Fig. 3:46 and Fig. 3:36 must always be shorter than the distance between Fig. 3:46 and the base of the strut Fig. 3: 50 on the base frame. In the particularly preferred variant in FIG. 6, the distance between FIG. 6B: 46 and FIG. 6B: 36 must always be shorter than the connection between FIG. 6B: 46 and the point FIG. 6B: 52.

If this distance is not given, the rotation of the paraboloid around point 46 can be limited or the mirror could not be completely closed in the rest position.

In this embodiment, the steering arms 42 are slightly curved, but this is not absolutely necessary. In the embodiment according to FIGS. 6A-6C too, the parabolic mirror is set up by moving the push blocks 40 to the left or to the right, depending on whether the mirror is to be pivoted up or pivoted down.

In summary, the following can be said. In this example, a semicircular, self-supporting reflector paraboloid 10 is suspended in one or more points 52 and in one or more further points 36 in such a way that a movement of the push blocks 40 carrying the points 36 (same number as the fastening points 36) along one through the Carrier of the base frame formed guide causes the scissors-like opening of the reflector 10. The thrust blocks 40 can be driven either individually or in combination. The drive can be arbitrary. Specifically, however, through a threaded rod that runs parallel to the rail 16 or 18, with a in the push block 40 Thread is attached and the movement is carried out by turning the threaded rod. The drive can also be achieved by a rack, toothed belt or chain, which is attached parallel to the rail 16 or 18 and a driven pinion, which is attached to the thrust block 40.

The attachment points 52 and / or the attachment points 60 are located within the reflector paraboloid. This results in a particularly compact structure. The entire mechanism can be attached below the paraboloid and is protected in the rest position.

The attachment of the receiver 62 can also be solved particularly simply in these systems. All it takes is the movable suspension in the inner corner of the paraboloid 10. When opening the system, the receiver simply grinds along the floor or along a simple slat until it is lifted from the lower edge of the paraboloid and is automatically in the focus of the paraboloid.

FIGS. 7 and 8 each show a triangular strut 80 which serves to stiffen the parabolic mirror 10, the triangular strut in FIG. 7 being designed to be used with an embodiment according to FIGS. 1 and 5, while in FIG. 8 the strut is attached to the Version is adapted according to Figure 6. There are two triangular struts for each parabolic mirror both in the embodiment according to FIG. 7 and in the embodiment according to FIG. 8, the number of triangular struts that are used being selected according to the number of steering arms 42.

In both embodiments, the three tips of the triangle 82, 84 and 86 come to lie at locations that correspond to the respective pivot axes 46, 60 or 36 are arranged adjacent. The triangular struts are preferably fastened to the brackets or blocks 38, 88 and 90 which accommodate the pivot axes 36, 60 and 46 and are also bonded or fastened to the parabolic mirror 10 or to the corresponding support structure 34. The positions of the pivot axes 36, 46 and 60 in relation to one another are clearly defined by the triangular struts.

FIGS. 9A and B show an arrangement according to the invention which essentially corresponds to the arrangement according to FIGS. 1 to 5, which is why the same reference numerals are used for the same components and the previous description also applies to the corresponding parts. Different from the embodiment according to FIGS. 1 to 5 in itself is mainly the design of the receiver 62, which now consists of two parts, namely a mirror 100 which is located in front of, in or behind the focal point of the parabolic mirror and a collector 102 which receives the rays reflected by the mirror 100 and therefore forms the actual receiver, which was arranged directly in the focal point of the parabolic mirror in the previous embodiment. The mirror 100 can also be a parabolic mirror or a spherically curved mirror. It can be seen that in this embodiment the collector 102 is arranged on the axis of rotation 32 of the base frame 14, so that it always has the same orientation to the mirror 100 and rotates about the axis 32 with the base frame. This applies regardless of the position of the parabolic mirror. The angular position of the mirror 100 must be selected accordingly for this purpose or automatically changed with the vertical sun tracking so that the same point is always irradiated on the receiver. In addition, the arrangement of the Steering arms 42 in FIGS. 9A and 9B are implemented somewhat differently than in FIGS. 1 to 5.

A particular advantage of this embodiment can be seen from FIG. 9A, namely that both the mirror 62 and the collector 102 are completely covered by the parabolic mirror 10 pivoted downwards, i.e. is protected.

It is particularly favorable if, in a departure from the illustration according to FIG. 9, the reflector 100 is arranged behind the focal point of the parabolic mirror below the arms 58, since it then does not stand in the way of the rays incident on the parabolic mirror and the efficiency is thereby higher. The reflector must then concentrate or distribute the rays coming from the parabolic mirror sufficiently over the collector. Receiver 62 can advantageously be located behind the focal point below arms 58 for the same reason, i.e. if only one collector and no reflector is used. The receiver can then advantageously be pivoted on the arms and be designed such that it is folded in or out during this movement into the closed position (FIG. 5A), resulting in a very compact arrangement.

FIGS. 10A and 10B show a further arrangement according to the invention, which is very similar to the arrangement according to FIG. 9A and 9B has, however, been implemented in accordance with the specific design of FIG. 6, ie that in this embodiment the steering arms 42 are located within the parabolic mirror. Since the receiver arrangement 62 in the FIG. 10 embodiment is identical to that in FIGS. 9A and 9B, a further explanation is not necessary; instead, the description of FIGS. 9A and 9B applies to the embodiment in accordance with FIGS. 10A and 10B.

Figures 11A to 11 J serve to explain the selection of the shape of the paraboloid.

Referring to FIG. 11A, the basic principle of a parabolic mirror is shown first. Incoming parallel rays 108, i.e. the rays that come from the sun and can be viewed as parallel rays 108 due to the distance of the sun are always directed to the focal point 110 of the parabolic mirror 10.

Figure 11B shows that the central area of the parabolic mirror, i.e. where the parallel light rays 108 are at least substantially perpendicular to the surface area 112 of the parabolic mirror 10, a more effective area is compared to an outer area 114 of the same dimension where the incoming parallel rays 108 are at a significant angle on the surface of the mirror fall. Here there is a geometrically given loss.

The amount of energy in the two groups of light rays 108 is the same. With the rays 108 that fall on the central region 112 of the parabolic mirror, energy is received in a region that is one

Width of any 30 units. This requires an area of the parabolic mirror that also extends over a width of approximately 30 arbitrary units. In the case of the parallel beams 108, which strike the area 114 of the parabolic mirror at the bottom, the corresponding area of the parabolic mirror must, however, have a width of approximately 41.80 units. have ten. In other words, more reflector surface area 114 is required than in area 112 to effectively reflect the same amount of incident light. It is therefore more economical to select a central region of the parabolic mirror for the purpose of the invention than a region which is further out, where the rays fall obliquely onto the mirror surface.

FIG. 1 IC shows, for example, how a parabolic mirror 10 with the shape shown in the previous figures can be formed from the central region of the parabolic mirror according to FIGS. 11A and 1 IB. It is particularly advantageous if the focal point 110 lies approximately in the horizontal plane 111 in FIG. 1 IC and is aligned with the lower edge 12, namely because the receiver can then be arranged in a favorable position.

Figure HD makes it clear that the parabolic mirror does not necessarily have to be realized as a continuous paraboloid, but that several segments, ie mirror facets 10A to 101, can be put together in order to produce an effective parabolic mirror. FIG. HD also shows the use of a receiver 62, consisting of a mirror 100 and a collector 102 in accordance with the embodiments of FIGS. 9A, 9B and 10A, 10B, and also shows how, in this example, the reflector 100 can have a flat mirror surface and above can also be arranged within the focal point 110 of the parabolic mirror realized by the segments 10A to 10E. This has the advantage that the dimension between the mirror 100 and the parabolic mirror 10A to 101 is shortened compared to the versions without a mirror 100, where the receiver is directly in the focus 110, which is very useful for the effectiveness of the parabolic mirror and the compact arrangement of the components when the parabolic mirror is folded down.

The figure HE shows how a parabolic mirror with an approximately rectangular shape can be imaged on the central area of a paraboloid of revolution. That the two hatched, approximately D-shaped areas above and below the central area 112 are "cut away", i.e. actually not made at all.

The dashed line 118 indicates a further possibility of dividing the central region 112 into two halves A and B, which can then be used for the purpose of the invention, if appropriate also arranged adjacent to one another.

The figure HF shows a further possibility of obtaining a parabolic mirror which is approximately rectangular in plan view. Here, too, the areas 120 with hatching are not used, but only the non-hatched area 10 below the center line 122, the lower edge 124 of the parabolic mirror 10, which is curved in FIG. HF, can be cut differently if desired, for example in accordance with the dashed line 124 ' , The upper half of the parabolic mirror according to Figure HF, i.e. the semicircular area above the center line 122 is normally not realized either, but merely serves to illustrate how a parabolic mirror 10 can be selected in relation to a parabolic mirror with a circular circumference.

However, FIG. HG shows that the area above line 122 could in principle also be used as a parabolic mirror, FIG. 11 H showing a view in the direction of arrow 126, which in practice is filled with the support structure 34, the figure 1 II shows how cutouts 128 in FIG Support structure 34 are possible, for example in order to arrange the parabolic mirror lower than in FIG. 3, so that the bars 16 and 18 are at least partially received in the cutouts 128. Such cutouts 128 can also be useful in order to enable a pronounced pivoting movement of the parabolic mirror about the pivot axis 36 without there being any contact between the parabolic mirror and the thrust blocks 40 or bars 16, 18.

Finally, FIG. 11J shows how the conditions for the curvature of the mirror can be selected most favorably.

In the selected example, r = 400 cm and the depth T = r / 4 = 100 cm. This ratio is important because it directly determines the relationship between the aperture (shadow on a vertical plane) and the mirror surface. With a ratio of T = r / 4, the mirror area is only about 10% larger than the aperture. With very large mirrors, a smaller ratio can be selected due to the better statics of the self-supporting paraboloid.

In FIG. 11J, the focal length of the parabolic mirror is equal to the radius r of the parabolic mirror. This design is very advantageous because it ensures that the receiver 62 and possibly the steering arms 42 are also covered in the pivoted-down state and that the curvature of the entire central region is not too strong.

FIGS. 12A to 12D show how the parabolic mirror can be composed of individual elements or segments. Here, it is assumed that the parabolic mirror is semicircular in plan view. However, it is understood that the outer outline of the para bolspiegel can actually be chosen arbitrarily, for example according to the different examples of Figures 11E, 11F and HG.

FIG. 12A first shows that the parabolic mirror 10 can be composed of five sector-shaped areas 142 “large segments” arranged one next to the other. Each segment 142 can consist of one piece or it can, for example, itself be composed of five individual pieces 144, as is shown for the bottom segment on the left-hand side of FIG. 12A. The left edge of the segment 140 on the left side can either be curved, as indicated at 146, or straight, as shown at 148. The individual pieces 144 can also be subdivided further and assembled from the different segments 150, which are shown on the right-hand side of FIG. 12A. Other subdivisions are also possible, as indicated by the lines 152 shown as an example.

It is intended to be expressed that the parabolic mirrors which are used for the invention can be manufactured in large dimensions, for example with a transverse dimension of more than 8 m. Such structures are relatively difficult to transport, especially since they are relatively light and could easily be damaged in the case of increased winds if they are not properly fastened to the transport vehicle. According to the invention, it is therefore preferred to produce the parabolic mirror from individual segments, which are then attached to one another at the assembly point of the parabolic mirror, as will be explained in more detail below.

Fig. 12B shows that the individual pieces of the sectors do not necessarily have to be executed with straight edges, but also two each may have curved edges such as 154 and 156. Of course, this does not apply to the sector-shaped segments 158 in the central region of the parabolic mirror. The individual segments within a ring are the same.

FIG. 12B also shows a further possible subdivision of a single sector, so that it consists of several similar pieces 160, wherein not all pieces 160 are necessarily the same, but in such a way that a sector 142 can be composed of a few segments 160.

12C shows the shape of the support structure 34 which can be used with a parabolic mirror according to FIGS. 12A and 12B, respectively in the direction of arrow 162 in FIGS. 12A and 12B.

Finally, FIG. 12D shows a schematic, perspective illustration of a parabolic mirror similar to FIG. 12B, from which it can be seen that the mirror surface can be composed of several segments 164, of which there are many types according to the number of rings, i. five varieties in this example.

A polystyrene extruder foam of higher density is preferably used as the material for the segments, which is provided on the reflective side with a reflective film, for example an aluminum film.

An example of such a segment, for example 152 according to FIG. 12A, but representative of the other sectors and segments 142, 144, 160, 164 of FIGS. 12A-D, is shown in FIG. 13. One notices that the segment 152 is provided on all sides with a rounded groove 170 which is in the form of a semicircular shape and extends over a little more than a semicircle extends. Such grooves can be cut out of the individual segments 152, for example, with minimal loss of material through the use of a heated wire, also shown in the form of a part circle. This results in approximately D-shaped parts 172 in cross section. It is then possible to glue two such parts to one another at point 174, which is shown in FIG. 13D. The structure 177 of FIG. 13D can be provided with an outer skin 175 made of fiber-reinforced synthetic resin. This skin 175 serves on the one hand to reinforce the connecting element and on the other hand compensates for the cutting width when the two D-shaped parts are pried out.

The structure of FIG. 13D with the cross section of the shape of an 8 can then be used again to glue two segments to one another. Since the dimension in the area of the arrows AA is greater than the dimension in the area of the arrows BB, which corresponds to the dimension at the entrance 176 to the grooves 170, it ensures a positive connection between two segments. According to FIG. 13F, each segment 152 can be provided on two sides with a structure 177 corresponding to FIG. 13D, so that the segments can be plugged together directly in accordance with a tongue and groove construction as is customary with base plates.

This part - as shown in FIGS. 13E and 13H - can also be used to attach a segment 152 to a rib part 180 which projects in the radial direction beyond the mirror surface (mirror film) 171 of the parabolic mirror and to stiffen the structure, i.e. of the parabolic mirror.

After several segments 160 have been bonded to one another, possibly using rib parts 180, the entire back is then covered a fiber reinforcement 181 is placed on the mirror, for example in the form of glass fibers, impregnated with an appropriate resin, so that a watertight, rigid shell is produced. This shell is stiffened on the one hand by the foam parts of the segments 152 and possibly the stiffening ribs 180, which are also made of foam or wood or other material, and also ensures that the segments themselves do not deform, so that the properties of the parabolic mirror are always ensured. Bolts 183 can be used to firmly hold the segments with reinforcing ribs together during the curing of the resin. If necessary, they can contribute to the strength of the finished structure or they can be removed again after the segments have adhered to one another (by means of the adhesive connection).

If desired, stiffening ribs 180 could be provided on the back of the parabolic mirror instead of on the front of the parabolic mirror 10 - or on both the back and the inside. There is no loss of effective area since the areas of the stiffeners are added to the mirror area. The mirror is therefore only slightly larger, but overall can help to stiffen the mirror, so that it can be built even larger and its effective surface area can be increased in this way.

The production of a shell from a composite material, for example glass fibers impregnated with resin, also makes it possible to attach the articulation lenses 38, 88 and 90 to the parabolic mirror. These tabs can namely also be realized as fiber-reinforced composite materials, if necessary with embedded bushings or metal or wood stiffeners, around the pivot axes with sufficient strength on the Attach parabolic mirror. Wood soaks up with synthetic resin and becomes particularly strong. Such a construction is easy.

The support structure 34 can also consist of composite materials and can also be bonded to the parabolic mirror using such fiber-reinforced layers.

Fig. 14 shows a first possibility of rotating the parabolic mirror, i.e. for the horizontal tracking in order to implement the vertical axis 32. The representation according to FIG. 14 largely corresponds to the representation according to FIG. 1, only the parabolic mirror and the associated steering arms have been omitted for the purpose of the representation. Otherwise, the base frame 14 is designed somewhat differently, to make room for the attachment of two motors 200 that drive two of the wheels 28 directly or via gears. Although two motors 200 are shown here, it would also be conceivable to work with only one motor 200. All the wheels 28 can also be driven. It can be seen that the two wheels 28 which are driven directly by the motors 200 are somewhat larger in diameter than the two other wheels 28. The reason for this is that one wants to make sure that the larger wheels 28 are always driving

Have contact with the guideway 30. The other two wheels serve only for stability and, because of the large dimensions of the base frame 14, will achieve their own contact with the guideway 30 by slightly bending the same, although the contact forces on the larger wheels 28 may be higher.

Equally sized driven wheels could also be lowered a little.

FIG. 15 shows a schematic illustration of a possible arrangement for displacing the push blocks 40 in order to adjust the vertical adjustment of the To reach the parabolic mirror. In this embodiment, a threaded rod 222 is used which is driven by a motor 224 to rotate. The rotational movement of the threaded rod 222 is transmitted via a nut element 226 to the driven thrust block 40, so that the latter, which is movably mounted on four rollers 228, can be moved in both directions along the respective bar 16 or 18, whereby to achieve the Movement in both directions motor 224 is a reversible motor.

The cross-sectional drawing according to FIG. 15B shows how the rollers 228 are mounted on stub axles 230, which protrude into the respective C-shaped spaces to the left and right of the central web 232 of the beam 16 or 18 realized as an I-beam, the rollers 228 run on the lower belt of the wearer.

In order to ensure the synchronization of the two thrust blocks 40 inexpensively and to get by with only one motor 224, the one threaded spindle 222 is driven directly by the motor 224 according to FIG. 15C - ie the threaded spindle 222, which is assigned to the carrier 18 in FIG. 15C - - While the spindle 222 assigned to the carrier 16 is driven synchronously with the directly driven spindle 222 via a chain 234. For this purpose, the chain 234 runs around two sprockets 236, 238 of the same size, the sprocket 236 on the spindle 222 being connected in a rotationally fixed manner to the output shaft of the motor 224 or the corresponding threaded spindle 222. The sprocket 238 is rotatably connected to the lower threaded spindle 222 in FIG. 15C. Finally, FIG. 16 shows an alternative possibility of driving the two thrust blocks 40 synchronously by a motor 224. Here, as in the embodiment according to FIG. 15C, the push blocks 40 are slidably mounted on the respective supports 18 and 16 with rollers. The details of this position rank correspond to those of FIG. 15 and are not shown further here.

The motor 224 drives a worm 240, which meshes with two worm wheels 242, which in turn shift the respective cables 244. The cables are connected to one of the push blocks 40 at respective fastening points 246 and have a respective tension spring 48 for length compensation and to ensure the required cable tension. Each cable 244 runs over a plurality of deflection rollers 250, which are shown schematically in FIG. 16.

16 gives the impression that the cables 244 would run around the respective worm wheels 242, the cables actually run around cylinders which are below or above the worm wheels. Although it would be conceivable that a sufficient driving force could be generated if the cables were only to extend half the circumference of the cylinder, it would probably be more favorable if the cables had several revolutions around the driving cylinder. Although this has the disadvantage that the cables are then moved in the axial direction of the cylinders when the cylinders rotate, since they are unwound, for example, from above and wound from below. However, this change in length can be compensated for by the tension spring 248.

It is particularly advantageous in the arrangement according to FIG. 16 that it is a very inexpensive solution, not only because rope trains are available relatively inexpensively, but also because the use of a worm drive consisting of the worm 240 and the worm wheels 242 enable a reduction, so that a relatively small, high-speed and inexpensive motor 224 can be used and the drive system is self-holding, ie there is no separate brake.

It should also be expressed that the outer contour of the parabolic mirror can by no means be realized only in a semicircle. In plan view, the parabolic mirror can have, for example, a rectangular shape or a rectangular shape with rounded corners, the rounded corners preferably being the two corners which are located away from the lower edge of the parabolic mirror during operation. Although in some of the examples shown here, the lower edge appears straight in plan view (since the one given by the parabolic shape

Curvature in this direction of view), it is also conceivable to give it a slightly curved shape.

A parabolic mirror which is circular in plan view can also be used for the purpose of the invention. This can be particularly advantageous if, for example, the parabolic mirror is to be used on a swimming pool that is approximately circular in plan view or on a house that is approximately circular in plan view, or is intended to cover a circular area of a swimming pool or house.

With such an arrangement, the articulation axis 46 is arranged at a position on the parabolic mirror which corresponds to a horizontal diameter of the parabolic mirror, so to speak, either at the front 5 or Fig. 6. The pivot axis 36 will then be in the region of the lower edge of the parabolic mirror in the raised position, preferably slightly above this lower edge. This is where the particular advantage of the invention comes in that the pivoting movement of the parabolic mirror is achieved by the mutual displacement of the articulation axes 46 and 36 towards and away from each other, so to speak.

As a result, the center of gravity of the mirror always remains approximately above the center of the support frame 14.

In the further description with reference to FIGS. 17-22, some preferred variants of the invention are described and the same reference numerals are used for the same parts as before, in order to avoid an unnecessary repetition of the description of the corresponding parts. This means that the previous description also applies here to parts that have the same reference numbers, unless something else is expressed. When new features are described, they are given new reference symbols.

FIG. 17 corresponds at least essentially to the representation according to FIG. 5E, but with the exception that the base frame 14 is raised at the front end 300, ie in the region of the pivot axis 36 when the parabolic mirror 10 is pivoted up, in relation to the rear end 302 , ie in relation to the area where the pivot axis 36 comes to rest when the parabolic mirror 10 is pivoted down. This will make the maximum swivel movement that is to be accomplished by the actuator between the completely swiveled down state parallel to the base frame 14 and the fully swiveled up state according to FIG. 17 in comparison to the embodiment according to FIG. 5, whereby the design of the actuator is positively influenced. This is particularly important when the sun is high - especially at the equator - because the parabolic mirror must be in a horizontal or almost horizontal position when it is swung up.

One way to achieve this inclined position of the base frame 14 is to attach the front wheels 28 to legs such as 304 that extend downward from the base frame 14. Another possibility would be to provide the front wheels 28 with a larger diameter as shown schematically at 28A, i.e. the base frame 14 is in this example at the front, i.e. on the side where the upper edge of the parabolic mirror comes to rest when swung down, increased by any substructure, e.g. through the vertical bar or leg 304, which can be braced for greater stability.

FIG. 17 also shows a rubber cable 306 that is stretched between the front end 300 of the base frame 14 and the receiver 62. The cable tension generates a torque around the pivot axis 36 in the swiveled-up state of the parabolic mirror 10 according to FIG. 17, which is the actuator when swinging down the parabolic mirror 10 helps to overcome the torque generated due to the action of gravity. Similarly, a rubber cord (not shown) can be stretched between the front end 300 of the base frame and the lower edge 308 of the support structure 34 when the parabolic mirror is swung down, which helps the actuator swing the parabolic mirror out of the swung down state. When swiveled up, this rubber rope will then go limp.

FIG. 18A corresponds approximately to the illustration in FIG. 5A, but in this embodiment the pivot axis 36 is attached to an upper support frame 310 of the push block 40, specifically at a location which is arranged in a recess 312 in the parabolic mirror. This recess 312, which is also shown in FIGS. 19A and 19B and of which there are two in this example (one recess for each push block 40), are each formed by two walls 314, 316, which in the side view have the shape of a right-angled triangle have and a distance "a" from each other. One side of each side wall is fixedly connected to the parabolic mirror 10, while the second side, which forms an at least substantially right angle with the first side, is connected to the support structure 34. The two hypotenuses 318 of the walls 314, 316 are connected to one another at 320 in order to achieve a rigid construction of the parabolic mirror. This means that each recess 312 extends from the intersection of the curvature of the parabolic mirror 10 with the support structure 34 to an imaginary line between the pivot axes 36 and 46 or an imaginary parallel line. This triangular recess can be made of wood, for example, or lined or formed and solidified with another solid material. In addition to the desired stiffening and reinforcement of the parabolic mirror, the recesses 312 allow the pivot axis 52 to be lowered, since the recess can accommodate the steering arm 42, which is not shown, however. Otherwise, due to the recess, the parabolic mirror 10 can also be pivoted further back in the swung-up state, since the upper support arm 310 of the push block comes to lie in the recess, as shown in FIG. 18B. It can be seen that the thrust blocks 40 which are used here are U-shaped in a side view, the legs of the U-shape lying horizontally, the lower leg carrying the rollers for the linear displacement of the thrust block 40 and the upper leg of the support arm 310 forms.

FIG. 19C shows that the parabolic mirror 10 has a notch wherever it could hit the base frame 14 or other parts such as the actuator with the lower edge 12 in the opened state. may be recessed as shown at 326 and 328 to avoid bumping.

FIG. 20A shows how a plurality of thrust blocks 40 (here two thrust blocks) can be driven with a number of actuators 224 (here an actuator) that differs from the number of thrust blocks. The two push blocks are namely firmly connected to one another, for example by means of a board or a rod 322, and the actuator 224 then acts on the assembly in such a way that the actuating forces are distributed uniformly over the two push blocks. To achieve this, in this example an actuator 224 engages the rod 322 in the middle thereof. The actuator 224 is preferably implemented as a garage door drive. The section BB shows how the push block 40 with two pairs of rollers 324 is attached to the side frame parts 326 of the base frame 14 so as to be linearly movable.

The solution proposed for the vertical sun tracking in this application for the first time could be described using the technical language of mechanical engineering as "linked gear with a thrust crank and three joints", the thrust crank being driven by an actuator. It is convenient to use a linear drive because the movement of the thrust crank is linear. As already mentioned, a commercially available garage door drive can be used for this purpose in a particularly cost-effective manner.

FIG. 21 shows an arrangement corresponding to FIG. 15C, but with additional parts in the form of the rubber cables 330. Each rubber cable is attached at one end 332 to the push block 40 or (which is not shown) to a structure which connects a plurality of push blocks 40. The second end 334 of each rubber cord is preferably attached to the base frame 14 in the middle of the travel distance of the push blocks. For better metering of the spring forces or rubber tension forces, several springs or rubber ropes such as 330 can be used, the second end of which is fastened at different positions on the base frame 14 along the travel distance of the thrust blocks. Basically, an arrangement of this type can be used with only one push block 40 or with several push blocks 40. At least one rubber rope 330 is then preferably provided for each push block. FIG. 22A shows a parabolic mirror 10 according to the invention, which is composed of individual flat, ie non-curved elements. In this example, the parabolic mirror 10 according to FIG. 22A consists of 6 concentric rings I, II, III, IV, V, VI. The ring I is composed of six segments 340 which are triangular in plan view. The ring II is composed of six segments 342 which are trapezoidal in plan view. The ring II consists of the segments 344 which are trapezoidal in plan view and the square segments 346, the trapezoidal segments 344 being very short at their inner ends and possibly being able to be replaced by triangular segments. The ring III in turn consists of elements 348 which are trapezoidal in plan view and square elements 346. Ring V in turn consists of elements 350 and square elements 346 which are trapezoidal in plan view and this also applies to ring VI which consists of elements 352 and square elements which are trapezoidal in plan view. dramatic elements 346.

The sides of the individual segments are chamfered so that the flat surfaces in the parabolic mirror are oriented so that there is a good approximation to the desired parabolic shape. The individual elements are glued to one another in the region of their sides to form segments, and the individual triangular segments 354 are likewise glued to the adjacent triangular segments 354 in the region of the long sides to form the parabolic mirror. According to FIG. 13, the entire structure is covered, at least on the back, with plastic reinforced with glass fiber, as shown in FIG. 13H, and the necessary recesses can be provided in the parabolic mirror ^" , which are described in connection with other figures. It is now shown with the help of FIGS. 22B and 22C how the construction according to FIG. 22A can be produced at least substantially without waste from extruder foam sheets such as A and here using elements 348 and 346 of ring IV, the explanation given here also for the Elements of the other rings apply.

A commercially available extruder foam sheet A, as is suitable for the present invention, can be obtained, for example, from the manufacturers in dimensions of about 60 cm wide x 240 cm long x 4 cm thick. Such extruder foam sheets are often provided with tongue and groove connections on their narrow sides, the lower narrow side 360 in FIGS. 22B and 22C being provided with a groove 362 and the upper narrow side 364 in FIGS. 22B and 22C being provided with a tongue 366 which is provided in a the corresponding groove 362 is inserted into the next panel. It is sufficient to simply plug the extruder foam panels together, optionally an adhesive connection can be provided in the area of the tongue and groove connection. In this way, an elongated structure is produced, as shown in FIGS. 22B and 22C, this structure being composed of individual plates, which is only indicated in the example of the lower plates, in order not to unnecessarily complicate the illustration.

Instead of forming the sheet web from several individual sheets such as A, it could be used as a continuous sheet from the foam extruder, which can then be divided into individual elements immediately after the extruder. The lower triangular region 368, which is shown hatched in FIG. 22B, is to be understood as a waste. Then the following elements are cut out of the material web formed by the plates in the order from bottom to top: 348, 346, 348, 348, 346, 348, 348, 346, 348, 348, 346, etc. In the area of the groove and Spring connection 362, 366 between two extruded foam sheets creates at least essentially no waste. That is, the taut area 368 only arises at the beginning of the first plate.

You can see from the double lines in the edge area of the individual elements as shown at 370 that the elements are beveled here. This applies to all areas that are drawn with a double line, whereby the degree of angling is to be selected according to the respective ring. A certain amount of waste may occur in some beveled areas, but this is minimal.

The dashed lines show edges which are formed on the underside of the plate web according to FIG. 22B.

Although the illustration according to FIGS. 22B and 22C only applies to ring IV, it is understood that a corresponding cutting scheme applies to the elements of the other rings. The waste, which is minimal, can also be melted down again, so that you can work without loss.

It is particularly favorable that some of the straight cuts, in particular those which run transversely or obliquely to the respective material plate or the material web, simultaneously the beveled, that is to say inclined, sides of two elements, which on the one hand minimizes material losses and on the other hand the cutting process can be carried out economically. The slant angles of slanted sides of the elements are each designed so that the approximate parabolic shape is created when the elements are put together. This means that the approximately radial sides of the elements of each ring have the same helix angle, but that the other sides of the individual elements, which run around the axis of rotational symmetry, are chosen differently by different rings depending on the position of the ring within the parabolic shape to create the desired approximate parabolic shape.

Although the parabolic mirror construction disclosed herein is primarily used for solar mirrors, the construction can also be used for other purposes such as radar systems or satellite reception.

Claims

claims

Concentrating solar energy system with a reflector (10) implemented as a biaxial tracking parabolic mirror, which is carried by a base frame (14) arranged in a supporting plane and with a receiver (62) arranged in operation before, after or after the focal point (110) of the parabolic mirror , wherein the parabolic mirror can also be rotated about an axis (36) arranged at least substantially perpendicular to the supporting plane, characterized in that the parabolic mirror has a lower edge (12) during operation, which is arranged at least substantially immediately adjacent to the supporting plane and in plan view either straight or slightly curved, and that the parabolic mirror (10) up and around a in the region of its lower edge (12) and at least substantially parallel to the support plane and linearly movable over the base frame (14) pivot axis (36) and is pivotable down.

Concentrating solar energy system according to Claim 1, characterized in that the parabolic mirror (10) can be swiveled down so far about the swivel axis (36) that it forms a roof when swiveled down.

Concentrating solar energy system according to claim 1 or 2, characterized in that the parabolic mirror (10) in the swung-down state on a wing, a foundation (30), a surface or a ner rests on the outline of the parabolic mirror (10) adapted wall and, if necessary, can be locked with this or with these.

Concentrating solar energy system according to one of the preceding claims, characterized in that an elongated supporting structure (34) extends along the lower edge (12) of the parabolic mirror (10) and stiffens the parabolic mirror as well as supports the pivot axis (36).

Concentrating solar energy system according to one of the preceding claims, characterized in that a triangular strut (80) is provided within the parabolic mirror with a connection at the intended articulation points (36, 46, 60) to a push block (40), on a steering arm (42 ) and on a support arm (58) of the receiver (62).

Concentrating solar energy system according to one of the preceding claims, characterized in that in order to implement the rotary movement about the vertical axis, the base frame can be rotated on a circular path (30) by means of rollers (28) or wheels.

Concentrating solar energy system according to claim 6, characterized in that the track (30) is defined and formed on the floor or on a foundation, on a wall, on a ceiling, on a rail or on a pipe frame. Concentrating solar energy system according to one of the preceding claims, characterized in that, in order to implement the pivoting movement, the parabolic mirror (10) is connected to the base frame (14) via a linkage arrangement (42) and the pivot axis (36) can be moved over the base frame (14).

Concentrating solar energy system according to claim 8, characterized in that the linkage arrangement consists of at least one steering arm (42) which at one end in the central region of the parabolic mirror (10) on the rear (at 46) and at the other end on a support point (52) is pivotally articulated from the base frame

(14) worn and arranged behind the parabolic mirror (10).

Concentrating solar energy system according to claim 8, characterized in that the articulation point (46) is located in the central region of the parabolic mirror in all unfolded positions of the parabolic mirror clearly above a line which is from the support point (52) to a articulation axis (36) on a thrust block ( 40) which is located in the region of the support structure (34).

Concentrating solar energy system according to claim 9 or claim 10, characterized in that two or more steering arms (42) are provided, which at respective locations on the back of the parabolic mirror (10) and at each Leagues of base frames (14) are supported pivot points (52).

Concentrating solar energy system according to one of claims 8 to 10, characterized in that at least two steering arms are joined together to form an A-frame which is pivotally articulated in the area of its tip on the back of the parabolic mirror and in the base area at respective support points.

Concentrating solar energy system according to claim 8, characterized in that the linkage arrangement consists of at least one steering arm (42) which at one end in the central region of the parabolic mirror

(10) on the reflecting inside and at the other end is pivotally articulated on a base (52) which is supported by the base frame (14) and is in the swung-down state of the parabolic mirror adjacent to the position which the upper edge of the swung-up state of the Parabolic mirror (10) assumes.

Concentrating solar energy system according to claim 13, characterized in that two or more steering arms (42) are provided which are pivotably articulated at respective points (46) on the inside of the parabolic mirror and at respective support points (58) on the base frame.

15. Concentrating solar energy system according to claim 13 or 14, characterized in that at least two steering arms are joined together to form an A-frame which is pivotally articulated in the area of its tip on the inside of the parabolic mirror and in its base area to respective support points,

16. Concentrating solar energy system according to one of the preceding claims, characterized in that for moving the pivot axis (36) on the base frame (14) is provided by a drive motor (224) driven actuator.

17. Concentrating solar energy system according to claim 16, characterized in that the actuator is a rotatably mounted threaded spindle (222) on the base frame (14), which engages in a corresponding thread or in a corresponding threaded nut in a thrust block (40) belonging to the structure supporting the pivot axis (36).

18. Concentrating solar energy system according to claim 15, characterized in that a threaded spindle (222) is assigned to each pivot bearing of the pivot axis (36) and engages in a respective thrust block (40). 9. Concentrating solar energy system according to claim 18, 57

characterized in that when a plurality of threaded spindles (222) are provided, these are driven synchronously or by means of a chain drive (234) driving both spindles simultaneously or by means of an incremental encoder and electronic control, e.g. HCTL 100 from HP, or with the help of pulse generators on the rail, which are evaluated by the control electronics.

Concentrating solar energy system according to claim 16, characterized in that the actuator is a chain drive, the chain revolves around two sprockets rotatably mounted on the base frame and is attached at one point in the region of the pivot axis to the parabolic mirror or to an associated thrust block.

Concentrating solar energy system according to claim 20, characterized in that a chain drive is assigned to each pivot bearing of the pivot axis and that the chain drives are driven synchronously, for example in that the drive sprockets are driven via a common shaft.

Concentrating solar energy system according to claim 16, characterized in that the actuator is a hydraulic drive.

Concentrating solar energy system according to claim 16, characterized in that that the actuator is a rack and pinion combination, the pinion being drivable by the drive motor and arranged on a thrust block assigned to the pivot axis.

Concentrating solar energy system according to claim 23, characterized in that an actuator is assigned to each thrust block (40) and that a device is provided to ensure that the pinions can be driven synchronously, for example that both pinions are driven by a drive motor (224) via a common one Shaft can be driven or with incremental encoder and electronic control, for example HCTL 100 from Hewlett Packard, or with the help of pulse generators on the rail, which are evaluated by the control electronics.

Concentrating solar energy system according to claim 16, characterized in that the actuator is a cable pull system which can be driven by a motor (224).

Concentrating solar energy system according to claim 25, characterized in that the motor (224) drives a worm gear (240, 242) which is coupled to the cable pull system (244).

Concentrating solar energy system according to claim 26, characterized in that the cable system consists of a cable (244) for each thrust block (40), each cable (244) being drivable by a worm wheel (242) which meshes with a worm gear (240) driven by the motor (224) of the worm gear.

Concentrating solar energy system according to one of Claims 25 to 27, characterized in that the cable pull (244) or each cable pull (244) can be wound up by the drive at one end and unwound at the other end.

Concentrating solar energy system according to one of the preceding claims 16 to 28, characterized in that the drive motor acts as a brake or has a brake in order to hold the actuator in the respective approached position.

Concentrating solar energy system according to claim 29, characterized in that the actuator has at least one worm gear (240, 242) which acts as a brake.

Concentrating solar energy system according to one of the preceding claims, characterized in that the receiver (62) is provided on one end of a support arm (58), the other end of which is articulated in the region of the lower edge (12) of the parabolic mirror (10), preferably on the mentioned PT / EP01 / 05743

60

Support structure and when swiveling up the parabolic mirror can be swung open.

32. Concentrating solar energy system according to claim 31, characterized in that the swiveling up of the receiver is carried out by bearing the support arm (58) on said support structure (34) or on an existing triangular strut (80).

33. Concentrating solar energy system according to one of the preceding claims, characterized in that the parabolic mirror in plan view is approximately semicircular, rectangular or rectangular with rounded corners, in the latter case in particular the corners facing away from the lower edge are rounded.

34. Concentrating solar energy system according to one of the preceding claims, characterized in that the parabolic mirror (10) has a shape which results from the cutting curve between a parabolic or semi-rotating body and a plane perpendicular to the axis of rotation of the rotating body. 5. Concentrating solar energy system according to one of the preceding claims, characterized in that the parabolic mirror is composed of segments, each of which consists of extruded foam bodies (polystyrene or the like). stand, which are covered on a flat or parabolically curved surface with a mirror film (179) and on the back with a skin (181) of a fiber-reinforced plastic, for example made of glass fiber and polyester resin, the segments (152) being joined together on their long sides or are joined together.

Concentrating solar energy system according to claim 35, characterized in that when using parabolically or spherically curved ones

Mirror surfaces, the parabolic or spherical shape is melted or cut into corresponding extruder foam sheets or that non-curved mirror surfaces are used, which determine the extent of the focal point by their size, which is particularly evenly irradiated in this case.

Concentrating solar energy system according to Claim 35 or 36, characterized in that the segments (152) are connected to one another on their long sides via form-fitting elements (177) which may also consist of extruded foam and are provided with a fiber-reinforced plastic skin (175).

Concentrating solar energy system according to one of Claims 35 to 37, characterized in that larger segments (142) which are joined or can be joined together to form the parabolic mirror (10) consist of a plurality of smaller, segments which have flat or curved surfaces (for example 152) can be put together or put together.

39. Concentrating solar energy system according to one of the preceding claims, characterized in that a liquid metal, for example zinc, as a heat carrier in the

Receiver is usable or used.

40. Concentrating solar energy system according to one of the preceding claims 1 to 38, characterized in that a liquid salt can be used or used as a heat carrier in the receiver (62).

41. Concentrating solar energy system according to one of the preceding claims 1 to 38, characterized in that a power-generating solar cell can be used or used as a receiver (62).

42.Concentrating solar energy system with a reflector realized as a biaxial tracking parabolic mirror, which is supported by a base frame arranged in a supporting plane and with a receiver arranged in operation in, before or after the focal point of the parabolic mirror, the parabolic mirror also being at least substantially perpendicular axis arranged to the supporting plane is rotatable, characterized in that that the parabolic mirror (10) can be swiveled up and down about a lower swivel axis arranged in the region of the support plane or at a distance above or below it, the swivel axis (36) being arranged so as to be displaceable in a plane parallel to the support plane or in the support plane and the displacement of the pivot axis (36) leads or contributes to the corresponding pivoting movement of the parabolic mirror (10).

Concentrating solar energy system with a reflector realized as a biaxial tracking parabolic mirror, which is supported by a base frame arranged in a supporting plane and with a receiver arranged in operation in, before or after the focal point of the parabolic mirror, the parabolic mirror also being at least essentially perpendicular to the supporting plane arranged axis is rotatable, characterized in that the parabolic mirror (10) can be pivoted up and down about a pivot axis (36) supported by the base frame and that the pivot axis is arranged in a plane parallel to the supporting plane for carrying out the corresponding pivoting movement.

Concentrating solar energy system according to claim 42, characterized in that the distance is within a range of + 25%, preferably

± 12.5% and in particular ± 10% of the maximum dimension of the parabolic mirror (10), whereby negative values mean that the pivot axis is below the supporting plane. Concentrating solar energy system according to one of Claims 42 to 44, characterized in that the pivoting movement is supported by at least one steering arm (42) and that when the parabolic mirror (10) is pivoted upwards, the latter is at one end on the parabolic mirror at a point (46) clearly above the supporting plane and is articulated at its other end to the base frame or to a base (52) attached to the base frame (14).

Concentrating solar energy system according to claim 45, characterized in that the or each steering arm (42) is at least partially arranged on the rear side of the parabolic mirror (10).

Concentrating solar energy system according to claim 45, characterized in that the or each steering arm (42) is at least partially arranged on the front, reflecting side of the parabolic mirror (10).

Concentrating solar energy system according to one of claims 42 to 47, characterized in that the parabolic mirror (10) appears circular or approximately circular in plan view or has a height / width ratio in the range between 0.5 and 1.5.

49. Concentrating solar energy system according to one of claims 42 to 48, characterized in that the displacement of the pivot axis (36) can be carried out such that the pivoting of the parabolic mirror (10) about the pivot axis (36) leads to the fact that the center of gravity of the Parabolic mirror (10) always lies above the base frame in the area of the base frame and preferably always in the area of the vertical axis of rotation (32).

50. Concentrating solar energy system according to one of claims 42 or 43 in combination with one or more of claims 2 to 41.

51. Concentrating solar energy system according to one of the preceding claims, characterized in that the base frame (14) is arranged inclined to a horizontal plane, the base frame (14) being pivoted upwards in the region of the pivot axis (36), i.e. in the swung-up state of the parabolic mirror. is higher at the front than further back, i.e. in the region of the swivel axis (36) when swiveled down.

52. Concentrating solar energy system according to claim 51, characterized in that the wheels (28A), which are arranged in the pivoted-up state of the parabolic mirror (10) in the region of the pivot axis (36), ie at the front on the base frame (14), have a larger diameter have as wheels (28) which, when the parabolic mirror is pivoted down, are arranged in the region of the pivot axis (36), ie at the rear of the base frame.

53. Concentrating solar energy system according to one of the preceding claims, characterized in that a spring (306, 330) or a plurality of springs, for example in the form of a rubber cable or several rubber cables, is or are provided in order to adjust the actuating force for pivoting the parabolic mirror

(20) provided motor (224) or the motors provided for pivoting the parabolic mirror.

54. Concentrating solar energy system according to one of the preceding claims, characterized in that one or more springs (306), for example in the form of a rubber cord or a plurality of rubber ropes, are provided, which are from the receiver (62) to the front part of the base frame (14) runs or run and in the swung-up state of the

Parabolic mirror (10) are excited. 5. Concentrating solar energy system according to one of the preceding claims, characterized in that one or more springs, for example in the form of a rubber cable or several rubber cables, is or are provided, which from the front of the base frame (14) to one in the area of Operation of the lower edge (12) of the parabolic mirror arranged support structure (34) for the parabolic mirror runs or run and is or are tensioned when the parabolic mirror is swung down.

Concentrating solar energy system according to one of the preceding claims, characterized in that the actuator (224) for the pivoting movement of the parabolic mirror is realized by a garage door drive.

Concentrating solar energy system according to one of the preceding claims, characterized in that when several are used, they support the pivot axis

Thrust blocks (40) with a number of actuators (224) which deviates from the number of thrust blocks, the thrust blocks (40) are firmly connected to one another and the actuator (224) or the actuators is or are connected to the network in such a way, that the driving forces are at least substantially evenly distributed over the thrust blocks (40).

Concentrating solar energy system according to claim 9, characterized in that in the region of the support point (52) of each steering arm (42) on

Base frame (14) a recess (312) is provided in the parabolic mirror, which from the intersection of the curvature of the parabolic mirror (10) with the lower edge during operation mirror ice up to an imaginary line between the swivel axis (36) and the articulation axis (46) of the respective steering arm (42) on the parabolic mirror or a line parallel to it.

59. Concentrating solar energy system according to claim 58, characterized in that each push block (40) carrying the pivot axis (36) has an upper support arm (310) which projects into the recess (312), the pivot axis (36) in the region of the recess (312) is attached to the parabolic mirror (10).

60. Concentrating solar energy system according to claim 59, characterized in that the recess is formed by two walls (319, 316) spaced apart from one another, each of which has an at least substantially triangular shape with two sides which are at an angle to one another Form a range of at least substantially 90 °, one of these sides being attached to the parabolic mirror (10) and the other to the support structure (34) for the parabolic mirror and the pivot axis (36) through the two side walls (314, 316 ) and through the upper support arm (310) of the push block (40).

61. Concentrating solar energy system according to one of the preceding claims, characterized in that the lower edge (12) of the parabolic mirror (10) has recesses (326, 328) in the area of the base frame during operation. Concentrating solar energy system according to one of the preceding claims, characterized in that the paraboloid mirror (10) consists of individual, non-curved trapezoidal elements (342, 344, 348, 350, 352 and 346) segments, the sides of which are straight and cut obliquely in shape that the elements joined to one another give the desired shape of the parabolic mirror and at least some of the straight cuts form the side shape of two elements each, whereby the elements joined to one another can cut the largely loss-free from a material plate or material web or from a material web composed of material plates are cut.

Use of a solar mirror as a roof and / or to illuminate a room underneath.

Method for producing an approximate rotational parabloid or a part thereof, characterized in that the rotational parabloid or a part 10 thereof is composed of a plurality of annular or partially annular regions (I, II, ... VI) such that each annular or partially annular region consists of is composed of several flat elements, which in

Top view are preferably trapezoidal, square and / or triangular, that the elements of at least one ring all have the same thickness and sides that are straight and cut in shape. ten are that the joined elements give the desired shape of the parabolic mirror and at least some of the straight cuts form the side shape of two elements, all elements of a ring being cut from a material plate or a continuous material web or from a material web composed of several material plates ,